<div class="container">
  <div class="interior">
    <a class="btn" href="#open-modal">👋 Basic CSS-Only Modal</a>
  </div>
</div>
<div id="open-modal" class="modal-window">
  <div>
    <a href="#" title="Close" class="modal-close">Close</a>
    <h1>
      Voilà!
    </h1>
    <div>
      A CSS-only modal based on the :target pseudo-class. Hope you find it helpful.
    </div>
    <br>
    <div>
      <small>Check out 👇</small>
    </div>
    <br>
    <a href="https://periphery.app?utm_source=codepen&utm_medium=web&utm_campaign=modal-pen" target="_blank">

      <img src="https://periphery.app/assets/wordmark-7b7617b2.svg" style="width: 120px">

      <div>
        <small>
        Build your ultimate wishlist while browsing the web.
        </small>
      </div>
  </div>
</div>
.modal-window {
  position: fixed;
  background-color: rgba(255, 255, 255, 0.25);
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  z-index: 999;
  visibility: hidden;
  opacity: 0;
  pointer-events: none;
  transition: all 0.3s;
  &:target {
    visibility: visible;
    opacity: 1;
    pointer-events: auto;
  }
  & > div {
    width: 400px;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    padding: 2em;
    background: white;
  }
  header {
    font-weight: bold;
  }
  h1 {
    font-size: 150%;
    margin: 0 0 15px;
  }
}

.modal-close {
  color: #aaa;
  line-height: 50px;
  font-size: 80%;
  position: absolute;
  right: 0;
  text-align: center;
  top: 0;
  width: 70px;
  text-decoration: none;
  &:hover {
    color: black;
  }
}

/* Demo Styles */

html,
body {
  height: 100%;
}

html {
  font-size: 18px;
  line-height: 1.4;
}

body {
  font-family: apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen-Sans,
    Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
  font-weight: 600;
  background-image: linear-gradient(to right, #7f53ac 0, #657ced 100%);
  color: black;
}

a {
  color: inherit;
  text-decoration: none;
}

.container {
  display: grid;
  justify-content: center;
  align-items: center;
  height: 100vh;
}

.modal-window {
  & > div {
    border-radius: 1rem;
  }
}

.modal-window div:not(:last-of-type) {
  margin-bottom: 15px;
}

.logo {
  max-width: 150px;
  display: block;
}

.btn {
  background-color: white;
  padding: 1em 1.5em;
  border-radius: 0.5rem;
  text-decoration: none;
  i {
    padding-right: 0.3em;
  }
}
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External CSS

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External JavaScript

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